The present invention relates to a waste stripping unit for stripping waste obtained by cutting a flat substrate. The invention also relates to a waste stripping unit that facilitates any stripping tool adjustment. The invention also relates to a packaging production machine comprising, in order and in succession, a cutting unit and a waste stripping unit. A packaging production machine is intended for the manufacturing of boxes, which form packaging after folding and gluing. In this machine, an initial flat substrate, such as a continuous strip of cardboard, is unwound and printed by a print unit, itself comprised of subunits in the form of printing units. The strip is then transferred into a cutting unit.
After cutting, the blanks obtained have areas of waste that are separated and discarded into a waste stripping unit, so as to be able to then create boxes after the waste is removed. The blanks are then separated in a separator to obtain individualized boxes.
The unit for stripping of these wastes is mounted after the cutting unit. The stripping unit ensures a precise and rapid stripping of wastes. The precision of operation of the stripping unit also makes it possible to avoid having waste cause jams.
The stripping unit comprises two tools, in the form of two rotary cylinders, positioned parallel to one another, so as to cooperate with one another. The blanks travel through a gap between the two cylinders following a substantially horizontal path.
One of the cylinders, the bottom cylinder, has radial needles which are pressed into each piece of waste. The needles separate the wastes from the blank by carrying them away with the rotation of the needle cylinder. These waste pieces are then removed from these radial needles during the rotation of the cylinders. Ejectors in the form of immobile combs are arranged parallel to the cylinders. The radial needles are thus freed of waste and will be pressed into other wastes when they next pass into the cutting area of the next blank.
The other cylinder, the top cylinder, has on its surface either strips made of a flexible material, for example foam, arranged in successive rings spaced apart, or a single strip forming a complete covering made of a flexible material, for example of vulcanized rubber type. Holes are pierced in the cylinder outside the areas covered by the foam strips or in the vulcanization layer, depending on the version. The position of the holes corresponds to that of the needles. These needles are accommodated in the holes as the two cylinders rotate, to ensure that the needles effectively pierce through the waste pieces. The top cylinder transports the blanks and holds them when the waste is spiked.